A light-receiving module is fabricated by sticking an optical fiber-supporting member and a photodiode-forming member together, in which lights emitted from light-emitting surfaces of optical fibers arrayed in parallel with each other at certain intervals on the optical fiber-supporting member are respectively received by light-receiving surfaces of photodiodes arrayed at the aforementioned certain intervals on the photodiode-forming member.
The optical fibers are respectively held between optical fiber-fixing grooves on the optical fiber-supporting member and optical fiber-positioning grooves on the photodiode-forming member in most cases. The lights emitted from the light-emitting surfaces of the optical fibers are respectively reflected by reflector surfaces formed at side ends of the optical fiber-fixing grooves and incident on the light-receiving surfaces of the photodiodes. However, the optical fiber-positioning grooves are formed by etching on a substrate in most cases, and then their surfaces are rough. Accordingly, positions of the light emitting surfaces of the optical fibers are fluctuated, and it sometimes occurs that the lights emitted from the light-emitting surfaces of the optical fibers are scattered by side edges of the optical fiber-positioning grooves and light-receiving efficiencies of the photodiodes decrease.